Terrible Experience

I already have a Cell C contract, decided to go with a second one and they tried to deliver it today. However, I only got an email and message from them saying they wanted proof of residence while at work, the delivery address. I did not have the proof of res but I did have my id and the courier refused to deliver it. I am astonished that even with me having a contract with them they require this again. There is and never has been a problem with my current contract. I then phoned them to cancel the whole thing and they wanted me to go into a cell c branch. I work 7 days a week and would not have the time to, he then said he would transfer my call to another department to do something or other, by that stage the courier had left with my phone. Why should this have been an issue with me having an existing contract . Clearly I am missing something, why must it be hard to do these things, why do they even have an online shop when things like this can happen. I do all my shopping online because I cannot get these places. I am now just waiting for Cell C to try and deduct the new contract installment. I bet you they do and then the struggle to get my money back begins